As slim disk drives incorporated in notebook personal computers and the like, there are a slot type (see FIG. 6A) that uses a DC motor to insert/remove a disk and a plunger type (see FIG. 6B) that uses a plunger to unlock a disk tray; a loading motor driver IC is required to correspond to both types.
In order to correspond to the slot type described above, it is necessary to switch the direction of an output current flowing through the DC motor according to the insertion/removal of the disk. Hence, as shown in FIG. 6A, a conventional motor driver IC 10 controls the terminal voltages of a first terminal LDOF and a second terminal LDOR according to an input signal LDIN (for example, (LDOF, LDOR)=(H, L), (L, H), (L, L)) such that an output current lout flows through a DC motor 11 connected between the first terminal LDOF and the second terminal LDOR either in a direction from the first terminal LDOF to the second terminal LDOR or in a direction from the second terminal LDOR to the first terminal LDOF or the output current Iout does not flow in any of the directions described above.
On the other hand, in order to correspond to the plunger type described above, it is necessary to pass the output current through the plunger when the disk tray is unlocked. Hence, as shown in FIG. 6B, with a plunger 12 connected to any one of the first terminal LDOF and the second terminal LDOR, the conventional motor driver IC performs the same terminal voltage control as described above (for example, (LDOF, LDOR)=(H, L), (L, H), (L, L)).
As an example of a conventional technology related to what has been described above, there is patent document 1.